That *can* be buffer bloat in action. It's just as often to do with the mostly-transparent base station roaming your phone does, its radio power management, the base station's load, the insane complexity of the HSPA+/HSPA/HSDPA/UMTS/GSM stack(s), the endless layers of weird and varied legacy crap that live under them, etc.
My phone will often poke away for a while trying to use a data connection, conclude it's not working, re-establish it, conclude it's still not working, switch to 2G (GPRS) and set that up, roam to a new base station as signal strenth varies, try to upgrade to 3G again, fail, and then eventually actually do what I asked.
Realistically, unless you're trying to do a google search while numerous other nearby people are watching TV / streaming video / downloading files / etc on their phones on the same network, it's probably more likely to be regular cellular quirks than bufferbloat.
As for power: Yep, the screen gets the blame for the majority of the power use on android phones. I can't help suspecting that means "display and GPU" though, simply because of the overwhelming power use. That's a total guess, but if GPU power is attributed under "System" then (a) it's insanely efficient and (b) Apple have invented new kinds of scary magic for their displays to allow them to run brighter, better displays for longer on similar batteries to Android phones.